Download Microprocessors

History of Computers - Long, Long
Ago
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beads on rods to count and calculate
still widely used in Asia!
History of Computers - 19th
Century
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first stored program metal cards
first computer
manufacturing
still in use today!
Charles Babbage - 1792-1871
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Difference Engine c.1822
• huge calculator, never
finished
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Analytical Engine 1833
• could store numbers
• calculating “mill” used
punched metal cards for
instructions
• powered by steam!
• accurate to six decimal
places
1948 and 1950s
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Transistor was invented in
1948 in the Bell Lab after
WWII. But in the early 1950s,
general purpose digital
computers were using
vacuum tubes to build basic
logic gates and flip-flops.
The vacuum tubes were
bulky, not reliable and very
hot.
The programmer actually
wired in the steps telling the
First Computer Bug - 1945
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Relay switches
part of
computers
Grace Hopper
found a moth
stuck in a relay
responsible for
a malfunction
Called it
“debugging” a
computer
Program Storage
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Later designs provide computer with
program storage. The only way of
knowing that some words are
program steps instead of data is to
check their location in memory.
Designers jumped at the change to
replace vacuum tubes with
transistors in the late 1950s. These
solid-state computers were already
much smaller, cooler, and more
First Transistor
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Uses Silicon
developed in 1948
won a Nobel prize
on-off switch
Second Generation
Computers used
Transistors, starting
in 1956
UNIVAC - 1951
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first fully electronic
digital computer
built in the U.S.
Created at the
University of
Pennsylvania
ENIAC weighed 30
tons
contained 18,000
vacuum tubes
Early 1960s
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In the early 1960s, minicomputers
were built for single kind of job.
Dedicated minicomputers were
found useful among scientists due to
cheaper cost and had real value.
A number of transistors were put on
one silicon wafer. The transistors
were connected together with small
metal traces – the building blocks of
integrated circuit (IC).
Integrated Circuits
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Third Generation Computers used
Integrated Circuits (chips).
Integrated Circuits are transistors,
resistors, and capacitors integrated
together into a single “chip”
Mid 1960s
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SSI and MSI (small and mediumscale-integration) produce families of
digital logic.
A small drawer size $10,000
minicomputers in the 1960s were as
powerful as the room size computer
of the late 1950s.
Microprocessors
In the early 1970, Digital computer
and solid-state circuit allows to
produce the microprocessors.
Digital Computer is a set of digital
circuits controlled by a program.
Solid-state circuit is a very large
scale integrated microcircuit - VLSI
The First Microprocessor –
1971
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The 4004 had 2,250 transistors
four-bit chunks (four 1’s or 0’s)
108Khz
Called “Microchip”
1970s
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Large-scale-integration (LSI) become
common.
By the 1980s, VLSI gave us with
over 100,000 transistors.
LSI were produced to perform
universal function such as memory
devices.
75 to 100 individual IC package for
the electronics calculators were
reduced to 5 to 6 LSI circuit.
Birth of Personal Computers - 1975
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256 byte memory
(not Kilobytes or
Megabytes)
2 MHz Intel 8080
chips
Just a box with
flashing lights
cost $395 kit,
$495 assembled.
Mid 1970s
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After the calculator size was reduce,
the next step was to reduce the
architecture of the computer to a
single IC – resulting circuit was
called the microprocessors.
Early microprocessors processed
digital data 4 bits at a time – slower
and did not compare to
minicomputers.
Apple Computers
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Founded 1977
Apple II released 1977
• widely used in schools
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Macintosh (left)
• released in 1984, Motorola
68000 Microchip processor
• first commercial computer
with graphical user interface
(GUI) and pointing device
(mouse)
1980s
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Complete 8-bit microprocessors were
developed. They become popular as
the basis of controllers for
keyboards, VCRs, TV, microwaves.
Then 16-bit and 32-bit were
developed.
Microprocessor’s instruction sets –
the instruction that microprocessors
can carry out – increased in size and
sophistication.
IBM PC - 1981
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IBM-Intel-Microsoft joint
venture
First wide-selling personal
computer used in business
8088 Microchip - 29,000
transistors
• 4.77 Mhz processing speed
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256 K RAM (Random Access
Memory) standard
One or two floppy disk
Generations of Electronic
Computers
First
Generation
Technology Vacuum
Tubes
Size
Second
Gen.
Transistors
Filled Whole Filled half a
Buildings
room
Third
Gen.
Integrated
Circuits
(multiple
transistors)
Smaller
Fourth Gen.
Microchips
(millions of
transistors)
Tiny - Palm
Pilot is as
powerful as
old building
sized
computer
Computers Progress
UNIVAC
(1951-1970)
(1968 vers.)
Mits
IBM PC Macintosh Pentium
Altair
(1981)
(1984)
IV
(1975)
2 Intel
Intel 8088 Motorola Intel P-IV
8080
Microchip 68000
Microchip
29,000
- 7.5 million
Microchip Transistors
transistors
Circuits
Integrated
Circuits
RAM
Memory
Speed
512 K
265 Bytes 256 KB
256 MB
1.3 MHz
2 KHz
Storage
100 MB
Hard Drive
8” Floppy Floppy
Drive
Drive
Size
Whole
Room
Briefcase
3200 MHz
= 3.2 GHz
Hard
Drive,
Floppy,
CD-Rom
Small
Tower
(no monitor)
4.77 MHz
Floppy
Drives
Briefcase Two
+ Monitor shoeboxes
(integrated
monitor)
Cost
$1.6 million $750
$1595
~$4000
$1000 $2000
Processor frequency trend
100
10,000
Intel
DEC
Gate delays/clock
21264S
1,000
Mhz
21164A
21264
Pentium(R)
21064A
21164
II
21066
MPC750
604
604+
10
Pentium Pro
601, 603 (R)
Pentium(R)
100
Gate Delays/ Clock
Processor freq
scales by 2X per
generation
IBM Power PC
486
386
1
2005
2003
2001
1999
1997
1995
1993
1991
1989
1987
10
 Frequency doubles each generation
 Number of gates/clock reduce by 25%
21st Century Computing
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Great increases in speed, storage,
and memory
Increased networking, speed in
Internet
Widespread use of CD-RW
PDAs
Cell Phone/PDA
WIRELESS!!!
What’s next for computers?
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Use your imagination to come up
with what the next century holds
for computers.
• What can we expect in two years?
• What can we expect in twenty years?
What is a microprocessor?
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Unlike full-scale CPU, the
microprocessor has digital logic
made up of one LSI. Since LSI and
VLSI are called microcircuits, it is
easy to see why microprocessors has
its name.
It is a micro-processing unit in
microcircuit form for data handling
and computation under program
control – data processing unit.
ALU
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Computation is performed by logic
circuits that make up the Arithmetic
Logic Circuit (ALU) – Add, Subtract,
AND, OR, Compare, Increment, and
Decrement.
ALU cannot itself move data from
place to place.
Like a blindfolded juggler – ALU must
wait for data to be placed in certain
places.
Control Logic
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In order to process data, the
microprocessor must have control
logic which tells the microprocessor
how to decode and execute the
program – a set of instructions.
It fetches them one at a time and
decodes the instruction. Then the
control logic carries out or execute
the decoded instruction.
It also controls how the
microprocessor works with memory,
input and output.
Microprocessors and
Microcomputer
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The microprocessor is never a
complete, working product by itself.
The microcomputer is a CPU based,
personal computer (PC).
Power of a Microprocessors
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Capability to process data.
• Length of the microprocessor’s data
word
• Number of memory words that the
microprocessor can address
• Speed the microprocessor can execute
an instruction
Length of Data Word
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Each microprocessor works on a data
word of fixed length.
Word lengths of 4 bits, 8 bits, 16
bits, and 32 bits are most common.
8-bit word length are common that it
has been given the name byte.
Some 16-bit microprocessor have
instruction s processed in two 8-bit
bytes.
Byte and Word
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4000 bytes on an 8-bit
microprocessor equals 4000 words;
on a 4-bit microprocessor, 4000
bytes equal 8000 words.
Each time the microprocessor’s word
length doubles, the processor
becomes more powerful.
4-bit microprocessors
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4-bit microprocessor is popular for
binary coded decimal (BCD) because
of extremely low cost.
Example: toys, calculators, simple
consumer products.
8-bit Microprocessors
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It is famous because
• The 8-bit word length is twice 4 bits,
• The 8-bits word length allows two BCD
numbers for each CPU data word, and
• The 8-bit length can hold all the data
needed for one character in the ASCII.
Number of Memory Word
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Each word in memory is assigned a
location number or address.
The larger the number of memory
addresses, the greater the
microprocessor’s power.
4 bits can address 16 words in
memory.
Common address ranges for 4-bit
microprocessors are 4096 and 8192
memory words.
Memory Word
8-bit microprocessors have an address
range of 65,536 memory words in the
65,536 bytes memory
 For the same memory size, 16-bit have
32,768 word memory.
Question:
A 16-bit word length is used by the 80286
microprocessor. If an 80286 addresses 32
kilo-words of memory, it memory will have
_____ bits of data
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Speed of Executes an
Instruction
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Microprocessors have a oscillator
circuit known as clock.
Slow microprocessors runs on a few
hundred kilohertz. It takes 10 to 20
microseconds to execute one
instruction.
Benchmark Programs
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Comparisons are more meaningful
when they find out how long a given
operation will take on the different
processors.